Sextus Empiricus Pyrrhoniae Hypotyposes 2.22.234

[234] And the method of leading up to the non-evident ¹ deals, they say, with the class of things that are variable. ² For when, according to the assumption, no previous question has been asked, the negation of the conjunctive premiss is true, the conjunctive or major premiss being false because of its inclusion of the false clause ‟I have asked you a question first.” But after the negation of the major has been asked, as the minor premiss ‟I have asked you a question first” has become true, owing to the fact that the negation of the major has been asked before the minor premiss, the first clause in the negation of the major becomes false while the false clause in the major has become true; so that it is never possible for the conclusion to be deduced if the negation of the major premiss does not co-exist with the minor premiss.